The importance of preventing fires in institutional settings has been recognized for many years, and a number of standards for flame retardance of mattresses and furniture have been promulgated.
A federal performance standard applicable to mattresses on a nationwide basis is codified in 16 CFR Part 1632 (Standard for Flammability of Mattresses and Mattress Pads), customarily referred to as the Cigarette Ignition Standard, the entire contents of which are incorporated herein by reference. However, even when mattresses meet the requirements of the Cigarette Ignition Standard, these can react with volatile and potentially deadly results when exposed to open-flame and smoldering ignition sources. The result can be a fire with sufficient energy to cause an average size room to reach a state of total instantaneous combustion or flashover. The California Bureau of Home Furnishings and Thermal Insulation has addressed the hazards associated with the ignition of mattresses in public institutions with California Technical Bulletin #129—Flammability Test Procedure for Mattresses for Use in Public Buildings (hereinafter ‘TB 129’), published in October 1992. It has since been adopted as a voluntary consensus standard by the American Society of Testing and Materials as ASTM E-1590 and the National Fire Protection Association (NFPA) as NFPA 267. (ASTM E-1590 and NFPA 267 use essentially the same test protocol as TB 129 but contain no failure criteria.) The standard has also been embodied in NFPA 101® Life Safety Code® 2000 and 2003 editions, section 10.3.4, and in Underwriter's Laboratories' UL 1895.
At the time that the U.S. Consumer Product Safety Commission (CPSC) was engaged in the review of mattress flammability that resulted in the 16 CFR Part 1632, it also conducted reviews of fire hazards posed by upholstered furniture. To stave off federal regulation, the furniture industry voluntarily formed UFAC—the Upholstered Furniture Action Council—in 1978, to allow upholstered furniture manufacturers the opportunity to work with CPSC to design safety standards that were effective, economical and workable from a manufacturing standpoint. The UFAC program is intended to make upholstered furniture more resistant to ignition from smoldering cigarettes that are the leading cause of upholstery fires in the home. The California Bureau of Home Furnishings and Thermal Insulation has addressed the hazards associated with the ignition of upholstered furniture in public institutions with California Technical Bulletin #133—Flammability Test Procedure for Seating Furniture for Use in Public Occupancies (hereinafter ‘TB 133’), published in January 1991. It has since been adopted as a voluntary consensus standard by the American Society of Testing and Materials as ASTM E-1537 and the National Fire Protection Association (NFPA) as NFPA 266. (ASTM E-1537 and NFPA 266 use essentially the same test protocol as TB 133 but contain no failure criteria.) The standard has also been embodied in NFPA 101® Life Safety Code® 2000 and 2003 editions, section 10.3.3.
Although hazards in public institutions have been addressed with standards based on TB 129 and TB 133, the number of injuries and fatalities associated with residential fires in which a mattress or upholstered furniture item was the first item ignited or the mattress exacerbated the fire event has led to efforts to reduce flammability of mattresses used in homes. One notable event is the passage of Assembly Bill 603 in the California Legislature of Assembly. The bill called for virtually all mattresses and sleep surfaces sold in the State of California, as of Jan. 1, 2004, to meet an open flame resistance standard and authorized BHFTI to take such steps as necessary to support the law. BHFTI published for comment in February 2003, California Technical Bulletin #603 (hereinafter ‘TB 603’), and subsequent to a mandated comment period and review of received comments announced TB 603's regulatory parameters as an amendment to Section 1371 in Title 4: California Code of Regulations. BHFTI also announced that TB603 implementation and enforcement would commence on Jan. 1, 2005. In addition, the Consumer Products Safety Commission is currently developing new regulations for further reducing mattress flammability beyond the level required by the Cigarette Ignition Standards. This was announced recently in the Federal Register (Advance Notice of Public Rule Making (ANPR) published Oct. 11, 2001)) The CPSC has also been engaged for nearly a decade in development of enhanced regulatory measures designed to reduce the flammability of upholstered furniture items.
The examination of mattress flammability has also resulted in concurrent evaluation of the flammability of bedclothes articles—specifically filled bedding articles, such as pillows, mattress pads and comforters. In California, the work to develop standards to regulate the flammability of these items has resulted in the formulation of Technical Bulletin #604. It is believed that the CPSC work on mattresses will follow this path as well and ultimately lead to some regulation of filled bedding articles on the national/federal level as well.
New standards for flammability of residential mattresses will require new materials and methods of manufacturing these, as mattresses targeted for residential markets differ significantly from those typically used in institutions. Institutional bedding installations typically require only a mattress and no foundation; mattress may be simply a solid core of polyurethane foam, which may be combustion modified to some degree as well. Many of the components used in institutional mattresses and sleep support surfaces, as well as furniture items, including fill materials and covering fabrics are subject to performance testing according to test criteria such as NFPA 701 and California Technical Bulletin No. 117.
One approach to reducing flammability of mattresses and upholstered furniture has been to treat fabrics used in their construction with chemical flame-retardants. However, these chemical treatments may be objectionable because of distasteful odors which are noticeable when in close contact with the materials, off-gassing obnoxious elements, stiffness of the fabric caused by such treatments, which may compromise the comfort of the finished mattress, mattress foundation or furniture item, and the potential temporary durability of such treatments, which may compromise the long term protection from open-flame, smoldering ignition and radiant/thermal heat flux sources.
Since 1993, widely used approaches to reducing the flammability of institutional mattresses and furniture articles have employed tubular knitted fabrics comprised of blends of modacrylic and fiberglass fibers as a fire barrier sleeve or sock that encapsulates the internal fuel load of the mattress and attempts to isolate it from the ignition source. Commercial offerings such as INTEGRITY30™ Fire Barrier Fabric by Ventex, Inc. of Great Falls, Va., KI-163™ FireGard® Fabric as manufactured by Chiquola Fabrics LLC of Tennessee and BlazeBlocker™ Fire Barrier Fabric sold by Herculite Products of Emigsville, Pa. are exemplary of such offerings.
Other approaches to achieving open flame resistant performance for mattresses and furniture typically incorporate fabric barriers comprised of fibers that are flame retardant in nature and that usually include modacrylic or pre-oxidized acrylonitrile (PAN) in the blend. AKTIV™ Fire Barrier Fabric is a needlepunched non-woven fiberglass and modacrylic blend manufactured by BGF industries and offered for sale by Ventex, Inc since 1996. Yet another offering is Barrier-F™ Thermal Insulating Fabric, manufactured and offered for sale by Ventex, Inc. a blend of modacrylic and FR-viscose rayon that may offer full scale, open-flame resistant performance in mattress only constructions and sets of bedding that represent relatively simple protective challenges. Leggett and Platt has offered its Pyrogon™ non-woven that includes PAN fibers as a key ingredient and offered this product for sale to mattress manufacturers and other producers of articles that are seeking enhanced levels of open flame resistant performance.
The versatility of these fabric fire barriers may permit them to be utilized as barriers to open flame ignition sources in a wide range of composite articles, including, but not limited to, mattresses, mattress foundations, sets comprised of mattresses and mattress foundations, upholstered furniture articles, filled bedding articles, such as pillows, mattress pads, and comforters, wheelchair cushions, healthcare positioners, and transportation seating.
In many end-product applications throughout the world, products ranging from mattresses to furniture to protective apparel to name a few, have selected modacrylic fibers, PAN fibers or chlorofibre/vinyon/PVC—based fibers as preferred ingredients in the design of barriers and protective components intended to isolate the end-products from the hazards of open-flame and smoldering ignition.
Recent public attention has been drawn to the hazards associated with the by-products of combustive activity. Notably targets of these activities are the products that contain chlorine or chlorine by-products and that when subjected to combustion and thermal decomposition, release toxic substances, including, but not limited to, dioxins and chlorinated dibenzofurans.
Dioxin represents a group of chemicals that includes furan and biphenyl compounds that are toxic waste byproducts of the burning of chlorinated waste and manufacture of other organic chemicals that contain chlorine, and which in itself has no commercial or industrial use (Courture, L. et al., 1990. A Critical Review of the Developmental Toxicity and Teratogenicity of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin: Recent Advances Toward Understanding the Mechanism. Teratology 41:619-627, 1990.) ‘Dioxins’ is a generic name given to a series of seventeen specific chlorinated dibenzo-p-dioxins and dibenzofurans in which chlorine is present at one or more of the 2,3,7,8 positions of the molecules. The tetrachlorinated dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) is believed to be the single most carcinogenic chemical known to science (Healing the Harm: Eliminating the Pollution from Health Care Practices, Health Care Without Harm Campaign Report, 1997; and Huff, 1994.)
Dioxin is dangerous to human health and is a known human carcinogen (International Agency for Research on Cancer (IARC) of the World Health Organizations, United Nations, 1997. National Toxicology Program Board of Scientific Counselors of the National Institute of Environmental Health Sciences, 1997.) The U.S. Environmental Protection Agency (EPA) estimates that the lifetime risk of getting cancer from dioxin exposure is above generally accepted safe levels (Mariani, Jay. Dioxin Fact Sheet, Environmental Law and Justice Clinic, Golden Gate University, San Francisco, 1998.), and the EPA's Dioxin Reassessment has found dioxin 300,000 times more potent as a carcinogen than DDT (the use of which was restricted in the U.S. in 1972) (U.S. EPA. Risk Characterization of Dioxin and Related Compounds; Draft Scientific Reassessment of Dioxin. Washington, D.C.: Bureau of National Affairs. May 3, 1994.); Dioxin has been linked to numerous other illnesses, including endometriosis, immune system impairment, diabetes, neurotoxicity, birth defects (including fetal death), decreased fertility, testicular atrophy and reproductive dysfunction in both women and men (Birnbaum, Linda et al. Developmental Effects of Dioxins and Related Endocrine Disrupting Chemicals. Experimental Toxicology Division, U.S. EPA. Toxicology Letters, p. 743-750, 1995.)
As a result of the attention paid to these issues a number of steps have been taken that aim to reduce the presence of products that contribute to the production and existence of dioxins and furans or at least increase the knowledge of the presence of such products. The 2000 Summer Olympics in Sydney were planned with an effort to minimize the use of chlorinated compounds. In Maine, outdoor burning of chlorinated compounds (notably PVC or vinyl based products) has been banned as these products when subjected to the incomplete combustion. In their effort to reduce the presence of chlorinated compounds, numerous companies and governments have enacted restrictions and material substitution policies aimed at reducing the presence of chlorinated compounds. Large companies such as Proctor and Gamble, Mattel, and the Body Shop have phased out packaging based on chlorinated compounds, specifically PVC based packaging. The Swedish Parliament voted in 1995 to phase out soft PVC and rigid PVC with additives that are already identified as harmful.
This trend toward voluntary reduction or regulatory elimination of chlorinated compounds may pose a threat to the continued use of modacrylic, PAN or chlorofibre/vinyon/PVC-based fibers in fire barrier applications. These types of fibers incorporate chlorinated compounds in their manufacture and the combustion of these fibers, in either normal use, intended use or in incinerative disposal, may result in the formation of chlorinated dioxins and furans. As a result, there is a need to develop products (e.g., mattresses, furniture and other filled articles) that achieve enhanced levels of flammability resistance but that do not rely on the use of fibers or raw materials that use chlorine compounds or by-products in their manufacture and that may threaten the potential release of dioxins and furans into the environment during production or disposal in attaining the enhanced performance levels.
There is work in other fields that seeks to derive benefit from switching to raw materials that have reduced chlorine content profiles in an effort to reduce dioxin production. US Application 2003087414 (Serial 10/109,091) filed Mar. 27, 2002, inventors Reiss and Schenk disclose a disposable diaper and method for making said diaper that is made from “non-chlorine bleached wood pulp” and is further described as being “totally chlorine free”. These attributes are cited by the referenced application as being preferred by “many people”. This work is limited to diaper and possibly personal/feminine hygiene applications by extensions and does not enter into the uses envisioned by the present invention.
U.S. Application 20030029589 (Serial 09/892,199) filed Jun. 25, 2001 (Altheimer & Jackson) discloses, “Total chlorine free bleaching of Arundo donax pulp”, the inventors describe the “elimination of precursor and reduction in chlorine application were found to be effective in bleaching pulp without dioxin formation.” This work is limited to composite panels of particleboard for construction applications and does not enter into the uses envisioned by the present invention.
Numerous examples of innovative design approaches to fire barrier design for mattresses and mattress foundations have recently been offered, including the following                a. Mason and Hale-Blackstone (20040062912) (10/262,133) filed Oct. 1, 2002        b. McGuire and Taylor                    i. (20040097156)(10/298,990) filed Nov. 18, 2002            ii. (20040102112)(10/714,370) filed Nov. 14, 2003            iii. (20040106347)(10/714,132) filed Nov. 14, 2003                        c. Mater and Handermann (PCT WO 03-023108) filed Sep. 11, 2002        d. Murphy and Slavik                    i. (20040060119)(10/291,879) filed Nov. 8, 2002            ii. (20040060120)(10/661,292) filed Sep. 12, 2003All of these works provide for the use of “FR Rayon” or “VISIL” in particular embodiments, however they do not draw a distinction or even make a provision regarding the use of FR viscose or rayon that is Totally Chlorine Free (TCF). Furthermore, as all of these rely on embodiments that specifically provide for the inclusion of modacrylic fibers (which through their manufacture incorporate chlorine atoms bound to the polymer structure), it is not reasonable to one skilled in the art that they would even contemplate the benefits to be derived from use of an ingredient that was an FR rayon or viscose that was specially formulated to be TCF.                        